A Dolton cop caught on camera allegedly breaking a 15-year-old special needs student's nose for failing to tuck in his shirt has a troubling history that includes killing a man in a case of disputed self-defense and is now in an Indiana jail on an unrelated rape charge.

Christopher Lloyd, 38, was identified Thursday by his father Charles Lloyd and Dolton Mayor Ronnie Lewis as the officer who in May was recorded by a school security camera scuffling with 15-year-old, 140-pound Marshawn Pitts at the Academy for Learning in Dolton.

An attorney hired by Pitts' parents released the video this week, calling the incident an "unprovoked attack" on a vulnerable child. The video, which has no audio, appears to show the officer slamming Pitts against a locker, wrestling him to the ground and pinning him.

But speaking Thursday, Charles Lloyd said he had seen the video and discussed the incident with his son, who he said was "just trying to do his job as a police officer and is completely innocent."

"My son said, 'Sir, you need to tuck your shirt in,' and this boy (cussed at him and said) 'I'm not going to tuck my shirt in, you can't make me,' " Charles Lloyd said.

"That boy struck my son in the eye and broke his glasses -- he had a history of behavior issues," he alleged.

Christopher Lloyd was arrested last month and charged with sexually assaulting a woman he knew at her home in Hammond, his father said.

According to Lake County, Ind., court documents, he held a pillow over the woman's face while sexually assaulting her Sept. 14 and had previously threatened her with a knife.

Lloyd, who's being held in lieu of $110,000 bail, faces up to 20 years behind bars if convicted of rape, criminal deviate conduct, criminal confinement and sexual battery, said Diane Poulton, spokeswoman for Lake County's prosecutor.

A lawsuit filed by his ex-wife, Nicole McKinney, last summer alleges he gunned down her new husband Cornel McKinney in front of their children outside their home on Feb. 17, 2008.

A Robbins police officer at the time, Lloyd was suspended after the shooting but eventually found work with Dolton police in January, his father said.

Though an autopsy shows he shot McKinney 24 times, the lawsuit alleges, he was not charged because Chicago police accepted his explanation that he had acted in self-defense.

Chicago police spokesman Veejay Zala said details of the investigation into McKinney's death could not immediately be found Thursday, but McKinney's attorney, Rahsaan Gordon, said the latest series of allegations against Lloyd showed he shouldn't have been employed as a police officer.

"At some point, people in positions of power need to protect the public," Gordon said. "You have to ask why he was hired."